1. Field of the Invention
Generally, the present disclosure relates to highly sophisticated semiconductor structures, and, in particular, to a resistor which has a resistance value substantially stable in a range of operating temperatures and a manufacturing method thereof. Further, the disclosure relates to the integration of such a resistor in a manufacturing flow, such flow optionally comprising the manufacturing of transistors having a metal gate.
2. Description of the Related Art
The fabrication of advanced integrated circuits, such as CPUs, storage devices, application specific integrated circuits (ASICs) and the like, requires the formation of a large number of circuit elements on a given chip area according to a specified circuit layout. Among the various elements, resistors are often needed.
The specific characteristic of a given resistor depends on its design features, such as its thickness, width and length, on its physical features, such as what implant base and materials are used, as well as the quantity of the implant. One physical feature intrinsic to any given material is the relation between its resistivity value and the operating temperature.
In particular, while a given material may have a nominal resistance value, its actual resistance is susceptible to changing as a function of the temperature of the material.
In particular, a material may experience a so-called positive temperature coefficient type of resistance, in which the resistance increases with the increase of the temperature, or a negative temperature coefficient type of resistance, in which the resistance decreases when the temperature increases.
In view of this situation, the present disclosure relates to a semiconductor structure and manufacturing techniques capable of obtaining a resistor which has a substantially stable resistance value, over a given temperature range, preferably as broad as possible, and further preferably without further incurring in the realization of steps in addition to those usually carried out in a CMOS process flow.